Railway-traffic-controlling apparatus



Oct. 11, 1927. 1,644,813

a. w. BAUGHMAN RAILWAY TRAFFIC CONTROLLING'APPARATUS Filed Nov. 1926 lifter Patented Oct. 11, 1927.

UNITED STATES PATENT OFFICE. A

GEORGE W. BAUGI-IMAN, OF EDGEWOOID BOROUGH, PENNSYLVANIA, ASSIGNOR TO THE UNION SWITCH & SIGNAL COMPANY, OF SWISSVALEPENNSYLVANIA, A CORPORA- TION OF PENNSYLVANIA.

RAILWAY-TRAFFIC-CONTROLLING APPARATUS,

Application filed November 1, 1926. Serial No; 145,399.

My invention relates to railway traflic controlling apparatus, and particularly to apparatus of the type comprising train carried governing means controlled by energy received from the trackway.

I will describe one form of apparatus embodying my invention, and will then point but the novel features thereof in claims.

The accompanying drawing is a diagrammatic view'illustrating one form of railway tratfic controlling apparatus embodying my invention.

Referring to the drawing, the reference characters 1 and 1 designate the track rails of a stretch of railway track traversed at times by trains provided with train carried governing means responsive to currents supplied to the track rails by means forming no part of my present invention and omitted from the drawing for the sake of simplicity. The control of the train carried governing means by the currents in the track rails may be accomplished as shown in the drawing through the medium'of a receiver R carried "-on the train V in advance of the forward axle 10. This receiver comprises two -magnetizable cores 3 and 8 located in inductive relation of the two track rails respectively. Gore 3 carries a winding't and core 3 carries a similar winding P, the windings 4 and 45 being connected in series in such manner that voltages induced therein by the train controlling current in the track rails, which currents are here assumed to flow in opposite directions in the two rails at an instant, are additive. The windings 4 and 4 are connected through an amplifier 5 of any suitable type with a relay A which may con trol the train carried governing means in any suitable manner.

In systems of the type described it is sometimes desirable to provide auxiliary circuits or loops at certain points in the trackway to which circuits current is supplied for testing the train carried apparatus or for producing certain effects in the apparatus independently of the currents in the track rails. For example, it may be desirable to. provide an auxiliary circuit in or about the terminal round-house for testing the train carried apparatus at the beginning or end of a locomotive run to determine if the apparatus will respond properly to train controlling current of a predetermined magnitude. As

shown in the drawing the auxiliary circuit comprises two conductors J and K located in the trackway adjacent the two rails re spectively and transposed adjacent the cen ters of the conductors as at B so thatthe right-hand portion J of conductor J is ad jacent rail 1 and the left-hand portion J of conductor J is adjacent rail 1*. manner the right-hand portion K of conductor K is adjacent rail 1 and the left-hand portion K of conductor K is adjacent rail 1. The conductors J and K are supplied with alternating current from secondary 6' of a transformer T, the primary 7 of which is constantly supplied with alternating current from a suitable source such as an alternator G over line wires 8 and 8 It will be plain from the drawing that current supplied to the auxiliary circuit flows in opposite directions in the two conductors J andK at a point in the trackway at any instant.

lVhen the train V is located over the auxiliary circuit the currents in conductors J and K induce in windings i and 4 voltages which affect the relay A in the same manner as the train controlling currents in the track rails. If the conductors J and K are supplied with a current of such magnitude as to create in the windings 4 and 4 voltagesof the same magnitude as are normally created in these windings by train controlling current in the track rails, the train carried apparatus including the relay A should respond in the same way as it, does to said train controlling currents. The auxiliary loop in the trackway therefore affords a convenient means for checking the operation of the train carried apparatus.

Without the transposition B in the conductors J and K however, there might be induced in the track rails due to the currents in' the conductors, currents which would have a large component displaced 180 degrees in phase from the currents in the adjacent conductors. The currents induced in the track rails would, of course, tend to neutralize the voltages induced in the receiver R by currents in the auxiliary loop. These induced currents would flow from rail 1 through the wheels and axles of train V, rail 1 and might flow back to rail 1 through the ground, or might return from rail 1 to rail l-through the wheels and axles of a second train V occupying the rails In similar adjacent train .V. The presence of these induced currents would be undesirable because it would make it impossible to determine Whether or not the train carried apparatus responded.properlyto normalvalues of current in the track rails. l/Vith the transposition B in conductors J and K, however, the current induced in rail 1 bycurrent flowing in the left-hand portion K of conductor K would be neutralized by the current induced in that rail by current flowing-in the righthand' portion J of conductor J, because the current fiows in opposite directions in the conductors J and K at an instant.

The auxiliary circuits of the type described are also used at times to control the train carried governing means in territory where the supply of train controlling current to the track rails is interrupted. In such instances, it auxiliary circuits are used without the transposition B the current induced'in the track rails may cause operation of the train carried apparatus before the train actually reaches the auxiliary circuit,

' the induced currents flowing down one rail,

through the wheels and axles of a train, back the other rail, and through the ground and ballast to the first rail. With an auxiliary t'raclnvay circuit provided with a transposition, and constructed in accordance with my inventio'n, this undesirable condition can not arise because the current induced in a rail by half of the auxiliary circuit isneutralized by the current induced in such rail by the other half ot'the auxiliary, circuit.

Although I have herein shown and described only one form of railway trafiic controlling apparatus embodying my invention, is understood that various changes and modifications may-be made therein within the scope of'the appended claims without departing from the spirit and scope or my invention.

Having thus described my invention, what I claim is:

1. Railway trafiic controlling apparatus comprising a pair of conductors supplied with alternating current which flows through the conductors in opposite directions at an instant, the conductors being located in the trackway adjacent the two track rails respectively and'beingtransposed with respect to the rails so that the currents induced in the rails'by current in said-conductors are neutralized.

' '2. Railway trail-fie controlling apparatus comprising a first conductor located in the trackway adj acentone'rail through one portion of track and adjacent the other rail through another adjoining portion of'track, a second conductor located in the trackway adjacent said one rail through said other portion of trackand adjacent the other railmeans for supplying the two conductors with alternating. current which "flows through the conductors in opposite direc tions at'corresponding pointsat an'in'stant, the result of the transposition of saidconductors being that the currentsinduced in the rails by current in the conductors are neutralized. i I

4. In combination, an auxiliary circuit located in the trackway and comprising two conductors parallel to the rails, and means for supplying alternating current to the conductors in series, saidconductors being transposed with respect to the rails so that the currents induced in the rails by current in the conductors are neutralized.

In testimony whereof I aifix my signature.

GEORGE W. BAUGHMAN, 

